Thread positioning means for button sewing machines



Aug. 13, 1957 J. H. JACKSON THREAD POSITIONING MEANS FOR BUTTON SEWINGMACHINES Original Filed Jan. 13, 1954 FIG. 3

.INVENTOR JOl-N H. JACKSON BY 4 A oazsv Patented Aug. 13, 1957 THREADPOSITIONING MEANS FOR BUTTON SEWING MACHINES John H. Jackson, Brooklyn,N. Y., assignor to American Machine & Foundry Company, a corporation ofNew Jersey Original application January 13, 1954, Serial No. 403,678,Divided and this application April 1, 1955, Serial No. 498,545

6 Claims. 01. 112-110 This invention relates to a sewing machine andmore particularly to a thread positioning means adapted to receive alength of thread, position it properly and make it substantiallyimpossible for this length of thread to get out of position where itmight be spitted by the needle or broken by operating parts of themachine.

This application constitutes a division of application Ser. No. 403,678,filed by Arthur G. Mirel on January 13, 1954, for Button SewingMachines.

The present invention consists in providing a sewing machine, such asdisclosed in Johnson et al. Patent No. 2,451,495, and in copendingPatterson and McGinley application S. N. 217,645, now Patent No.2,739,550, dated March 27, 1956, with a thread trap and a thread lockadapted to function during operation of the machine in alwaysmaintaining the thread properly disposed with respect to the needle andoperating parts which come in contact with the thread so that breakageof the thread is substantially eliminated.

While reference is made to the above referred to Johnson et al. patentand Patterson et al. application, it is understood that the invention isnot limited in use solely to the type of the machine disclosed insuchpatent and said application.

According to the form of the invention illustrated herein, the loose endof the thread which is pulled through the work, in a sewing machineprovided with opposed upper and lower alternately operating needle barsadapted to pass a needle back and forth through the work, is providedwith a thread trap located adjacent the upper position of the lowerneedle bar such that when the thread puller pulls the loose end of thethread through the work, this end of the thread is disposed on a supportforming a part of the thread trap.

The thread which is used in a button sewing machine of the typedisclosed in the patent and application above referred to and copendingapplication S. N. 403,678 is cut in lengths from a spool of thread. -Ithas been'found that the' lengthof thread has a tendency to coil. inconformity v with the coiling of the thread'onthe spool from which itiscut. Thus" the thread tends to move out of the position where it canbe moved into the thread trap, and out of the path of the movement of athread lifter which is provided to dispose it in the thread trap.

In order to insure that the thread will be properly located in thethread trap, there is mounted on the support a spring-urged lockingfinger having a bar portion adapted to be engaged by the end of thethread lifter. When the thread lifter is located in its inoperativeposition, the end of the thread lifter engages the bar portion of thefinger and holds it against the tension of the spring out of closingposition with respect to an opening in the thread trap through which thethread is moved by the thread puller.

As the thread lifter moves into engagement with the thread on thesupport, the thread locking finger moves 700, it is also laid across ahook-shaped lifter finger 702 forwardly under the action of itsoperating spring to close the opening above referred to thereby makingit impossible for the thread to twist or move out of the thread trap. Itwill be seen therefore that the thread when thus disposed is positivelylocked in the thread trap against removal therefrom.

It is an object of the invention to provide a novel thread trap andmeans for disposing and locking a length of thread in said trap againstinadvertent or unwanted removal during the operation of a sewingmachine.

It is a further object of the invention to provide a novel threadcontrolling mechanism for a sewing machine wherein a length of thread ispositively controlled and prevented from unwanted lateral displacementout of a thread trap during the operation of the sewing machine.

With these and other objects not specifically mentioned in view, theinvention consists of certain combinations and constructions which willbe described fully hereinafter, and then set forth in the claimshereunto appended.

In the accompanying drawings which form a part of this specification andwhich like characters of reference shall indicate some or like part;

Figures 1 and 2 are isometric views illustrating the successivepositions of a thread control mechanism embodying the invention, duringthe operation of the machine; and

Figure 3 is a partial plan view of some of the elements shown in Figures1 .and 2.

Referring to the drawings which show a preferred embodiment of theinvention selected for purposes of illustration, the sewing machine withwhich the invention associates and which forms a part, is provided witha thread receiving drum 700 on which the loose end of a length of threadis adapted to be disposed by means of a'thread puller 168 duringalternate operations of the upper and lower needle bars 58 and 60.

The construction and operation of the machine with which the presentinvention is readily adaptable for use is similar to the type disclosedin Johnson et al. Patent Number 2,451,495. Such machine is provided withan upper needle bar 58 and a lower needle bar 60 and a thread disposingdrum or surface or groove 700 on which the loose end of a thread ofdiminishable length is adapted to be laid by thread puller 168 duringalternate movements of the needle bars, when the machine is inoperation. Since the specific structure for operating needle bars 58 and60, and finger 702 do not form a specific part of the invention, andsuch mechanism is fully shown in the patents and applications abovereferred to, further showing and description are omitted as beingunnecessary to a full understanding of the invention.

In order to prevent entanglement of the loose end of the thread withthread puller 168, or possible spitting by needle 142, the machine isprovided with a thread control mechanism, which is illustrated inFigures 1 and 2 of the drawings. As the loose end L of the thread T islaid by the thread puller 168 onto thread trough or drum which islocated in front of thread trough 700 and which is secured to anoperating arm (not shown) pivotally mounted on a stud (not shown) onmain base 50. The

free end of the operating arm carries a cam follower is moved upwardlyas well as rearwardly, causing that portion of the thread which passesthrough the material to engage with a stationary thread guide lug 712,and a suitablyshaped trap 714, attached to block 716, pref- 3. erabl'yformed integrally with a member 708 secured to main base 50; In order toguide the thread into trap 714 and prevent it from slipping out of thesame, a suitably shaped lock finger 720 works in. conjunction with and.

follows the lifter. finger 702 as soon. as the latter startsto movebackward...

Lock finger 720 is mounted on a stud shaft 722 which.

is loosely supported in thelower portion of trap. 714. Lock finger 720.is .also provided with plate. or lug .724,

the. top edge of which is in engagement .with the lower:

front edg'efof lifter finger 702 whichholds lock finger. 720 inuprightposition asilong as finger 702 is inaits foremost position. As.soon as thewlatter moves rear- Wardly, I a suitable. tension. spring.7'26. urges lock. finger. 7203rearwardly until.the:top edge of. plate724-.engagese the frontedgeof. the. lowerportionof the trap.,714 and.thejtrap is: closed. Thus the-trapped lengthxof.thread.

cannot move or twist laterally out of trap 714.

Whatl claimis:

l. Ina. sewing machine of the type described having. an upper needlebar. and a lower. needle. bar adapted to.

passa needle andathreadback. and forth through work to be stitched, athread receiving surface located adjacent said lower needle.-bar,.amember having. aanarrow thread supporting ledge located adjacent said.lower needle bar. and above. said. surface, a thread puller for pullingthe loose end of said thread. through said work and. disposing it.uponsaid. surface, a thread trap located.

adjacent said ledge, a device located adjacent said'ledge. formovingsaid loose-endof saidthread disposed on said surface to positionsaid threadifor delivery into said trap in response to the upwardmovement of said upper needle bar, said upward movement of. said upperneedle bar also locating. said; thread on said ledge, and. a threadlock. member positioned. adjacent said trap adapted. to

move towards said thread trap to lock said. thread against movement awayfrom said thread trap.

2. The invention definedin claim 1 wherein: said thread.

lock member comprises an arm, meanspivotally mounting said. arm on saidthread trap. for movement to and from said thread trap, meansnormallytending to urge said.

armtowardslocking engagement :with said: threadvtrap,

and means on said arm engaged by said device, prior to the operation. ofsaid device, for maintaining said arm outof threadlockingrelationshipwith said' thread trap..

3...In a sewingmachine. of the; typehaving a' work support. table, anupper needle bar and a lower, needle bar. adapted to pass aneedleand athread back and'forth through work to be stitched, a thread receivingsurface mounted adjacent said. lower needle bar having, aleading and.atrailing end, a; member'- having a thread supporting. ledge.positioned. adjacentsaid. surface longitudinally. spaced from saidleading end of said surface,

means mounting said member at one side of said lower:

needle. bar, a thread puller forpulling the loose end of said threadthrough saidwork and disposing'it. upon said. surface, a thread traplocated adjacent said leading 4. In a sewing machine of the typehavinga-work.

support table, an-upper needle 'bar and at lowerneedle bar adapted topass a needle and a thread back: and forth through work to be stitched,a thread receiving surface having a portion located adjacent said lowerneedle bar, and a threadpull'er forpulling the looserend of said threadthrough said work and disposing it upon said surface, a membermountedabove-said surface having a thread supporting ledge, a thread traplocated adjacent said ledgeandsubstantially alignedtherezwtth, ardevicemounted. for movement: above; said; surface; for. moving said looseendof said thread; disposed'torn saidldrum to' position. said; thread;for. delivery :into: said' trap. and on. said. ledge in :response: to;th'ewupwardzmovernenti of I said" upper needle bar, a-threadilockmembertpositi'oned above said. surface andadjacent said'lower needlebar,1 and meansoperative in response" to the movement ofsaid device todispose saidl thread :on. said; surfacefor moving said lock. member:into operativesrelationship withsaid thread lock.

5: In a. sewing;gmachine of the; type having. a; work support table;an;upper needle-.bar. and'a lower needle bar adapted to; pass: a needle:and; a: thread back and forth through; work. to be: stitched, ..a.threadreceiving:

surface-mounted. adjacentsaid'; lower: needle: bar, and: a

thread puller; for pulling. the loosezend of said. thread through saidwork and: disposing-it: upon :said: surface; .athread traplocatedadjacent saiddoWen-needle; bar"and along the path of traveloftsaid'thread pullena'devic'e movably: mounted above A said surface."for: moving: said loose end of. said: thread: disposed; on; saidisurface: to posit-ion. said thread 'for delivery; into-saidlZIKPJiDJ'IESP'OHSfi to the upward movement of said upper needlerbar,and

a thread. lock-member mounted-above; said surface: and operative inresponse 'to' the. amovementrofisaid device. to move. towards saidthready trap: and. lock said thread against movement. away;.fromr.sairtthread trap;

.6. Therinventionzdefinedin claim 5; including a thread 7disposing-finger carriech byrsaidihreadipuller; and means-- formountingnsaidi finger on said: thread puller so' as to disppserthe.loose end of the thread :pulleibyraid thread puller properly: on; said.thread receiving; surface.

References. Cited inlthei. file of thispatent: UNITEDJS'FATES PATENTS?1,369.,371' Allen Feb... 22,} 1921 2,210,638 Spaine et al. Aug. 6; 1940'2,250,973" Spaine etial. July 29; 1941- 2,301,798"

Sp'aine et.'al Nov. 10, I942

